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ACRO E-mail Archive Thread: [Acro] Re: S-2B engine temps?

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ACRO E-mail Archive Thread: [Acro] Re: S-2B engine temps?


Thread: [Acro] Re: S-2B engine temps?

Message: [Acro] Re: S-2B engine temps?

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From: "Terry Burch" <zlinman.woody at>

Date: Mon, 23 Sep 2002 16:53:06 UTC


  Doug,  this is pretty normal for an injected engine.  It has to do with un
equal cylinder flow.  Tons of reasons why, none you can do anything about.
If the nozzles were perfect, you get all cylinders to peak at the same time.
The temps would still be different.  No one used to worry about it because
we never had instruments accurate enough to tell. Woody----- Original
Message -----
From: <DSowder at>
To: <acro at>
Sent: Sunday, September 22, 2002 10:22 PM
Subject: [Acro] S-2B engine temps?

> Is anyone else flying an S-2B with a 6-cylinder engine analyzer? I put a
> EDM-700 analyzer on my B at the same time the engine was rebuilt, and have
> put 420 hours on it since. The No. 1 cylinder always has the coldest EGT
> CHT, no matter what the power setting or how I lean. EGT is about 60 to 90
> deg. colder than #4 (usually the hottest), and CHT is about 30 or 40 deg.
> colder. This despite swapping injector nozzles, EGT and CHT sensors. The
> 1 cylinder seems to peak at about the same mixture setting as the other
> cylinders, it's just always colder.
> For some reason this is bothering me more these days. It would seem that
> only answer is that #1 is getting less air for some reason, but it seems
> would make it run richer and thus peak much later (i.e. with the mixture
> control pulled further out). It's run this way since "sort of new"; I
> flew the airplane before this engine rebuild. The engine is strong and
> smooth, and compression is excellent. Just curious to know if anyone else
> sees a similar temperature spread.
> Thanks,
> Doug Sowder


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